Background/Aim: To identify the best of three isatin-based scaffolds in terms of anticancer activity. Materials and Methods: Synthesis of isatin-based scaffolds was performed through a reaction to form Schiff bases. In silico analyses consisted of a target prediction with the Swiss Target Prediction tool and a molecular docking by AutoDock Vina. Anticancer activity and cytotoxicity were determined using the WST1 viability assay. Results: Three scaffolds (IA, IB, and IC) were synthesized and confirmed with good reaction yields. The Swiss Target Prediction tool showed a trend towards kinases. Molecular docking assays demonstrated higher affinity of IC towards CDK2. Anticancer activity assays identified IC as the most active against the cancer cell lines. Cytotoxicity results in non-cancer cells suggested a lack of selectivity. Conclusion:The scaffold IC was identified as the best in terms of anticancer activity and these effects may be due to inhibition of CDK2, as evidenced by molecular docking.

Many therapies have been developed against COVID-19 since it first appeared in December 2019. Antivirals, antimalarials, cephalosporins, colchicine, anticoagulants, corticosteroids, among others, have been evaluated as protecting agents against antibacterial complications due to their anti-inflammatory and immunomodulatory effects against thrombosis and cell death caused by infection with SARS-CoV-2. Nevertheless, the overall balance in their application has not been found to be satisfactory. On the other hand, the development and application of several vaccines against this virus have marked an important watershed in preventive and prophylactic medicine in the new millennium. However, given the regular efficacy reported of some of them, the still scarce affordability, and the emergency of new strains for which no drughas been evaluated, the search for new pharmacological therapy alternatives still represents an essential component in the clinical management of COVID-19, and the rapid identification of drugs with potential antiviral and/or immunomodulatory properties is needed. In the present review, a potential therapeutic effect of metformin and other antidiabetic therapies for the management of COVID-19 are proposed and discussed from the viewpoint of their in vitro and in vivo immunomodulatory effects. Given that acute inflammation is an important component of COVID-19, antidiabetic therapies could be promising alternatives in its management and for reducing the severity of the disease. In order to understand how metformin and other antidiabetic therapies could work in the context of COVID-19, here we review the possible mechanisms of action through a detailed description of cellular and molecular events.

At least half the population in industrialized countries suffers from obesity due to excessive accumulation of adipose tissue. Recently, rice (Oryza sativa) proteins have been considered valuable sources of bioactive peptides with antiadipogenic potential. In this study, the digestibility and bioaccessibility in vitro of a novel protein concentrate (NPC) from rice were determined through INFOGEST protocols. Furthermore, the presence of prolamin and glutelin was evaluated via SDS-PAGE, and their potential digestibility and the bioactivity of ligands against peroxisome proliferator-activated receptor gamma (PPARγ) were explored by BIOPEP UWM and HPEPDOCK. For the top candidates, molecular simulations were conducted using Autodock Vina to evaluate their binding affinity against the antiadipogenic region of PPARγ and their pharmacokinetics and drug-likeness using SwissADME. Simulating gastrointestinal digestion showed a recovery of 43.07% and 35.92% bioaccessibility. The protein banding patterns showed the presence of prolamin (57 kDa) and glutelin (12 kDa) as the predominant proteins in the NPC. The in silico hydrolysis predicts the presence of three and two peptide ligands in glutelin and prolamin fraction, respectively, with high affinity for PPARγ (≤160). Finally, the docking studies suggest that the prolamin-derived peptides QSPVF and QPY (−6.38 & −5.61 kcal/mol, respectively) have expected affinity and pharmacokinetic properties to act as potential PPARγ antagonists. Hence, according to our results, bioactive peptides resulting from NPC rice consumption might have an antiadipogenic effect via PPARγ interactions, but further experimentation and validation in suitable biological model systems are necessary to gain more insight and to provide evidence to support our in silico findings.

Metabolic reprogramming in cancer is considered to be one of the most important hallmarks to drive proliferation, angiogenesis, and invasion. AMP-activated protein kinase activation is one of the established mechanisms for metformin’s anti-cancer actions. However, it has been suggested that metformin may exert antitumoral effects by the modulation of other master regulators of cellular energy. Here, based on structural and physicochemical criteria, we tested the hypothesis that metformin may act as an antagonist of L-arginine metabolism and other related metabolic pathways. First, we created a database containing different L-arginine-related metabolites and biguanides. After that, comparisons of structural and physicochemical properties were performed employing different cheminformatic tools. Finally, we performed molecular docking simulations using AutoDock 4.2 to compare the affinities and binding modes of biguanides and L-arginine-related metabolites against their corresponding targets. Our results showed that biguanides, especially metformin and buformin, exhibited a moderate-to-high similarity to the metabolites belonging to the urea cycle, polyamine metabolism, and creatine biosynthesis. The predicted affinities and binding modes for biguanides displayed good concordance with those obtained for some L-arginine-related metabolites, including L-arginine and creatine. In conclusion, metabolic reprogramming in cancer cells by metformin and biguanides may be also driven by metabolic disruption of L-arginine and structurally related compounds.